VulnerabilityPublished 26 Feb 2026Updated 27 Feb 2026

CVE-2026-27141: golang.org/x/net/http2 · NULL Pointer Dereference

Affects golang.org/x/net/http2Source CVE Database V5

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Not known to be exploited · CVSS 7.5 High : upgrade to 0.51.0 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 0.51.0

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 26 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade golang.org/x/net/http2 to 0.51.0.

Affected software

Product	Affected	Fixed in
golang.org/x/netgolang.org/x/net/http2	Affected >=0.50.0 <0.51.0	Fixed in 0.51.0
Gogolang.org/x/net/http2`pkg:golang/golang.org/x/net/http2`Other threats	Affected =0.50.0	Fixed in–
Gogolang.org/x/net/http2`pkg:golang/golang.org/x/net/http2`Other threats	Affected >=0.50.0 <0.51.0	Fixed in 0.51.0

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate CVE-2026-27141, organizations should promptly update the golang.org/x/net/http2 package to a patched version once it is released by the maintainers. In the interim, developers can implement defensive programming techniques such as adding explicit nil checks before dereferencing pointers in the HTTP/2 frame processing code. Network-level mitigations include deploying Web Application Firewalls (WAFs) or HTTP/2-aware proxies that can detect and block malformed or suspicious HTTP/2 frames with types 0x0a to 0x0f. Rate limiting and anomaly detection on HTTP/2 traffic can reduce the risk of exploitation attempts causing denial of service. Additionally, monitoring server logs for unexpected panics or crashes related to HTTP/2 frame handling can provide early warning signs. Organizations should also review their incident response plans to quickly address potential DoS events stemming from this vulnerability. Finally, consider disabling HTTP/2 support temporarily if feasible and if the risk of exploitation outweighs the benefits of HTTP/2 performance improvements.

Description

Due to missing nil check, sending 0x0a-0x0f HTTP/2 frames will cause a running server to panic

Impact

The primary impact of CVE-2026-27141 is denial of service due to server crashes triggered by malformed HTTP/2 frames. Organizations running web servers or services that depend on the vulnerable golang.org/x/net/http2 version 0.50.0 may experience unexpected outages, leading to service unavailability and potential disruption of business operations. This can affect customer trust, revenue, and operational continuity. Since the vulnerability can be exploited remotely without authentication, attackers can easily cause widespread disruption. Additionally, repeated exploitation attempts could lead to resource exhaustion or complicate incident response efforts. Although the vulnerability does not directly compromise confidentiality or integrity, the availability impact alone is significant for critical infrastructure and high-availability services. The lack of known exploits in the wild suggests limited current exploitation, but the ease of triggering the issue means risk could increase rapidly once public proof-of-concept exploits emerge.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 21:49 UTC

WeaknessesCWE-476

Technical details

References

Community reviews

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